*** Posted by run ***
Super sonic flight is flying above the speed of sound. Breaking the sound barrier is passing the speed of sound.
The speed of sound at sea level is 1224 km/h which equals 661 knots (NM/h) if we are talking Statute miles per hour it is more like 760. Mach two is twice the speed of sound.
The speed of sound changes with altitude.

run

[Terminology:
Does Super Sonic Flight and Breaking the Sound Barrier imply the same meaning. Super Sonic does have a more polished sound to it?? At sea level what airspeed would you have to attain in order to "break the sound barrier". Preferably in miles per hour or mathmatical formula to translate knots to kilometers per hour/miles per hour. Does Mach 2 imply your traveling twice this speed? I've heard/read in order to break the sound barrier you would have to exceed approximately 725 miles per hour at sea level.

Thanks,
Chris]